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Updated: Feb 24, 2026
08:04
Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
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Tower of Structured Excited States from Measurements
Yuxuan Guo1, Yuto Ashida1,2
1University of Tokyo, Department of Physics, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Physical Review Letters
|February 22, 2026
Summary
Researchers developed a new measurement-based method using global observables to create highly entangled quantum states. This approach efficiently generates quantum many-body scar states and other complex states for quantum information science applications.
Area of Science:
- Quantum Information Science
- Condensed Matter Physics
- Quantum Computing
Background:
- Preparing highly entangled quantum states is crucial but challenging.
- Previous methods relied on local observables, limiting efficiency.
Purpose of the Study:
- To introduce a novel measurement-based protocol for efficient entanglement generation.
- To leverage global observables for preparing structured excited states.
Main Methods:
- Utilized quantum phase estimation to measure global observables (magnetization, momentum) via local measurements.
- Developed a log-depth protocol suitable for various quantum platforms.
- Integrated theoretical insights with experimental feasibility.
Main Results:
- Successfully generated quantum many-body scar states in diverse models (AKLT, XX chains).
- Enabled preparation of high-weight Dicke states and the Arovas A state.
- Demonstrated feasibility with few-bit gates and limited postselection.
Conclusions:
- Measurement-based approaches using global observables are powerful for accessing highly excited quantum states.
- This method has potential applications in quantum metrology, error correction, and studying quantum dynamics.
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